A bill aimed at preventing guns from being sold to people legally barred from owning them drew fire Tuesday night in Annapolis, as gun rights advocates charged the measure would simply let state authorities drag out sales now delayed for months because of a large backlog in Maryland State Police background checks.

The bill by Del. Jon S. Cardin, a Baltimore County Democrat, would require that a prospective gun owner's background check be complete before the weapon's sale, transfer or lease, regardless of how long that takes.

But dozens of gun owners and advocates signed up to testify against the bill before the House Judiciary Committee, which held a marathon hearing on gun legislation, saying legitimate gun purchases should not be blocked because of the state's own ineptitude at doing background checks.

Cardin did not appear to explain his bill, sending an aide instead. Joshua Greenfield, his legislative director, said by the time the committee got around to his bill he had returned to Baltimore Tuesday evening to pursue his campaign for the Democratic nomination for attorney general.

He put the bill in after The Baltimore Sun reported that more than 200 guns had been sold to people who shouldn't have had them during an unprecedented surge in gun purchases before Maryland's tough new gun law took effect last October. One of those handguns was used in an armed carjacking, state police disclosed.

Under current law, gun dealers may release guns to buyers after seven eight days even if the background checks has not been completed, unless the dealer has reason to believe the buyer is ineligible. In introducing his bill in January, Cardin said he wanted to close what he considered a "loophole" in the law that allows ineligible individuals to obtain handguns.

State police received 128,630 applications to acquire guns last year, the vast majority before the Oct. 1 effective date of the Firearms Safety Act, which bars the sale of some semiautomatic assault-type weapons and imposes new training and fingerprinting requirements and fees on handgun purchases. The volume of applications overwhelmed state police capabilities to do background checks, causing months-long delays and a backlog that peaked last fall at 60,000 checks.

The backlog had been cut in half by January and as of last week stands at 10,140, with police still processing reviews from late September. Police have said the expect to eliminate the backlog by late spring.

Gun-rights advocates and even a few committee members bristled at Cardin's bill, saying it would punish legitimate gun buyers for a problem they contended was caused by the state police.

"It was the policy of the Maryland State Police that put hundreds of guns on the street," suggested Del. Kevin Kelly, an Allegany County Democrat.

Cynthia Firman, of Ellicott City, argued in prepared testimony that further delays in processing gun transactions would be "an immense infringement" on citizens' constitutional rights to have weapons.

Del. Michael D. Smigiel Sr., an Eastern Shore Republican, offered a competing bill, which would allow gun sellers to check a federal online database at the time of sale, instead of having to submit paper applications for the state police to review. Using the federal system, which many other states rely on, would have prevented improper releases, Smigiel contended, and would have allowed sales to be handled on the spot, rather than requriing lengthy waits.